Reciprocating dies for straightening parts



Feb. 11, 1958 r R. D. BERG 2,822,854

RECIPROCATING DIES FOR STRAIGHTENING PARTS Filed Sept. 29, 1954 l I 34; I .L. III II lfiiiiiii" 23 3 i M/mww/P ATTORNEY United States Patent P RECIPROCATING DIES FOR STRAIGHTENING PARTS Richard D. Berg, Westchester, Ill., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application September 29, 1954, Serial No. 459,180

4 Claims. (Cl. 153-48) This invention relates to a device for straightening parts and more particularly to a pair of relatively reciproca-ble dies having cooperating surfaces for straightening parts therebetween.

An object of the invention is to provide a device for straightening parts.

A further object of the invention is to provide a pair of relatively reciprocable dies having cooperating surfaces for straightening parts therebetween.

A device illustrating certain features of the invention for straightening piece parts may includes a pair of relatively reciprocable dies having shallow flutes formed in the opposed faces thereof with the ridges on the flutes disposed in parallel relation to each other and in parallel planes and with the flutes of one die laterally offset relative to the ridges of the other die, whereby the fluted surfaces of the dies serve to press a part therebetween and bend successively adjacent parallel portions thereof slightly in oblique relation to each other to form a slight corrugation in the part which disappears when the dies separate and renders the part straight.

Other objects and advantages of the invention will become more apparent by reference to the following detailed description and the accompanying drawings illustrating a preferred embodiment thereof, in which- Fig. 1 is a fragmentary elevational view of the die assembly for straightening parts;

Fig. 2 is a 'bottom plan view of the upper die;

Fig. 3 is a plan view of the lower die;

Fig. 4 is an enlarged fragmentary vertical sectional view through the upper and lower dies in operative position with a piece part therebetween; and

Fig. 5 is a perspective view of a part which is to be straightened.

The present device was designed to straighten parts such as piece parts 12 punched from a sheet of metal for use in fabricating machines such as typewriters, adding machines, etc., which parts may be relatively small and of various shapes and of which it is essential that they be perfectly flat and straight to within relatively small limits. The straightening device 10 comprises a pair of upper and lower dies 14 and 16 secured to upper and lower die holders 18 and 20, respectively, which are guided for relative reciprocable movement by guide pins 22. The cooperating lower and upper surfaces of the upper and lower dies 14 and 16, respectively, are provided with a plurality of adjacent parallel flutes or grooves 23 forming corrugated straightening surfaces 24 and 26. The corrugated or fluted straightening surfaces of the dies are formed by grinding a series of adjacent concave shallow cylindrical flutes or grooves in the straightening surfaces with the ridges 28 of the flutes disposed in parallel relation to each other. The ridges 28 on the upper die are disposed in staggered relation with respect to the ridges 28 on the lower die so that the ridges of the upper die are mounted for vertical recipro- 2,822,854 Patented Feb. 11, 1958 cation in planes disposed midway between the ridges on the lower die.

The piece parts 12 are adapted to be laid on the lower die lengthwise thereof so that the part is positioned across the ridges thereof and when the upper die is moved downwardly and presses the part against the lower die, the ridges 28'on the fluated straightening surfaces engage the part 12 along parallel lines on opposite sides thereof and in staggered relation to each other and impart a slight bending movement to adjacent parallel portions thereof as shown in Fig. 4. The depth ofthe flutes and the lateral spacingof the ridges are so related that they bend the piece part slightly into corrugated shape which disappears when the dies are separated and leaves the parts in straightened condition. During the straightening of a part, portions of the parts are pressed by the ridges 28 on each of the dies into engagement with the opposed concave surfaces of the other dies as shown in Fig. 4 and the parts are subjected to compression. The compressive stresses which are applied to the parts vary for parts of difierent materials and may be light for some and heavy for others in order to obtain the straightening of the parts.

In one embodiment of the invention which has proved satisfactory for straightening small piece parts, the flutes or grooves 23 were ground to a depth of .0015" with the ridges 28 spaced apart approximately of an inch. The parts 12 placed between the cooperating dies are thus but slightly in opposite directions at intervals of approximately of an inch to an extent which serves to straighten the flat piece part without imparting any irregularity thereto.

If desired, means may be employed to aid in positioning the part advantageously on the die. As shown herein a gage member 30 is inset in the lower die for engaging in a slot 32 at one end of the piece part 12 and another gage 34 is inset in the lower die to engage the opposite end of the piece part. The gages extend upwardly above the ridges 28 a distance less than the thickness of the piece part 12 so that they do not contact and interfere with the movement of the upper die.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of this invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

l. A device for straightening parts comprising a pair of dies having cooperating opposed straightening surfaces engageable with opposite sides of the parts and each die being provided with a plurality of parallel concave cylindrical grooves of substantially less depth than the thickness of the parts being straightened and with the junctures of the concave grooves forming ridges disposed in a plane and having substantially line contacts with the parts, and means for mounting said dies for relative reciprocation with the ridges of the dies in parallel planes and with the ridges of the movable die disposed for reciprocation in planes midway between the ridges of the other die.

2. A device for straightening parts comprising a pair of dies having cooperating opposed straightening surfaces engageable with opposite sides of the parts and each die being provided with a plurality of parallel concave cylindrical grooves of less depth than the thickness of the parts being straightened and with the junctures of the concave grooves forming ridges disposed in a plane and having substantially line contacts with the parts, means for mounting said dies for relative reciprocation with the ridges of the dies in parallel planes and with the ridges of the movable die disposed for re ciprocation in planes midway between the ridges of the other die, and gage means on one of said dies for positioning the parts in a predetermined location thereon.

3. A device for straighteningpartscomprising apair of dies having opposed cooperative corrugatedstraightening surfacesengageablewith'opposite sides of the fiat parts and forming a plurality of parallel uniformly spaced ridges and shallow grooves of substantially less depth than the thickness of the parts being straightened and with the ridges of each -die disposed in a plane, means for mounting said dies'for relative reciprocation and with the ridges of the-straightening surfaces and the planes thereof in parallel relation to each other and with the ridges-of one die disposed opposite the grooves of the other die for heading and compressing the parts therebetween.

4. A device-for straightening parts comprising a pair of dies having opposed cooperative corrugated straightening surfaces engageable with opposite sides of the-flat parts and forming a plurality-ofparallel uniformly spaced ridges and shallow grooves ofsubstantially less depth than the thickness of the parts being straightened and with the ridges of each die disposed-in a plane, means for mounting said die for relative reciprocation and with the ridges of the straightening surfaces and the planes thereof in parallel relation to each other and with the ridges of one die disposed opposite the grooves of the other die for bending and compressing the parts therebetween, and-gage members mounted on one of said dies for positioning the parts in a predetermined location on the die.

References Cited in the file of this patent UNITED STATES PATENTS 9,278 Presser Sept. 21, 1852 236,853 Somers Jan. 18, 1881 652,658 Bischoflf June 26, 1900 1,525,908 Beans Feb. 10, 1925 FOREIGN PATENTS 394,908 Great Britain July- 6, 193:3

U. S. DEPARTMENT OF COMMERCE PATENT OFFICE CERTIFICATE OF CORRECTION Column 3, line 16, for "heading" read ben'ding u Signed and sealed this 24th day of June 1958,

(SEAL) At fiest:

KARL Hg AHINE ROBERT c. WATSON Attestlng Officer Comnissioner of Patents 

